Chromosomes are the genetic material of the human body, and any person carries autosomes and sex chromosomes in his or her body. The sex-related chromosomes are the sex chromosomes. The sex chromosomes carried by males are the XY chromosomes and the sex chromosomes carried by females are the XX chromosomes, which means that the sex chromosomes of females are the X chromosomes. The genes carried on the chromosomes are directly related to the development of congenital hereditary diseases. Genes for autosomal inherited disorders are found on the autosomes, while genes for sex chromosomal inherited disorders are found only on the sex chromosomes. When there is clinical suspicion that a fetus may have a chromosomal abnormality disorder, chromosomal DNA testing of the fetus is required. When there is a suspicion that a fetus may have a sex chromosome inherited disorder, the fetus needs to be examined for sex chromosomes. Testing regarding sex chromosomes cannot be done without a medical indication.